Diffuser assembly for non-turbulent air flow

ABSTRACT

The invention is an air flow diffuser that produces an even and non-turbulent flow of air from ventilation or A/C. The diffuser combines a pressure chamber and a discharge chamber to produce a non-turbulent even flow of air perpendicular to the face of the discharge chamber. The pressure and discharge chambers are contiguous with the ducted air flowing first into the pressure chamber and then into the discharge chamber from which chamber the non-turbulent, evenly flowing air flows into the space. Though the diffuser is developed for a downward air flow, the diffuser can be constructed in several shapes, such as triangular, allowing air flow in any direction that is perpendicular to the plane of the discharge plate.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not Applicable

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT

Not Applicable

REFERENCE TO SEQUENCE LISTINGS

Not Applicable

BACKGROUND OF THE INVENTION

This invention is in the field of endeavor dealing with ventilation withspecific air distribution.

Current air supply diffusers are designed with deflectors or louvers fordirectional flow so as to direct air flow to specific areas of a spacewithout regard to turbulence and contained air flow. This directed airflow is acceptable for basic heating, cooling, ventilating and/or othersimilar applications within an enclosed space. However, drafts and otherturbulent conditions may be created which may prove to be “unacceptable”for applications in certain environments. Therefore a more controlledand non-turbulent air flow is required for providing a more comfortableor even distribution of air.

BRIEF SUMMARY OF THE INVENTION

The invention resolves the issue of turbulence and dispersion ofdelivered air. It causes the flow of supplied air to be smooth, evenlydistributed, and perpendicular to the face of the diffuser. A specificproblem the invention solves is the cross ventilation that occurs whenlouvered or deflector controlled air flow bounces off walls, beams andother surfaces. For example, this air movement particularly affects anopen flame or heated cooking surface where the fumes should risevertically by convection from the heated area into an exhaust hooddirectly above the heated surface. Any cross ventilation diverts thesmoke, fumes and heat producing convection currents, even with anexhaust fan in the hood, such that the capture of these products by theexhaust hood is disturbed, preventing the exhaust hood from capturingall the elements.

Simply increasing the air flow in the exhaust hood causes increased airturbulence in the space around the exhaust hood and does notsignificantly increase the amount of emissions collected by the exhausthood. In addition, increasing the flow in the exhaust hood, requiresadditional make-up air and a subsequent increase in A/C and/orventilation capacity, but still does not solve the problem of smoke,heat and fumes migrating into the space around the exhaust hood.Providing a non-turbulent air flow, in proximity of the exhaust hood,eliminates the cross ventilation issues caused by current make-up airsupply diffusers.

The invention regulates and directs air flow by pushing air into thespace by pressure as opposed to deflecting the space make-up air fromthe ventilation or A/C supply air source. To accomplish this, a pressurechamber is created in the top of the diffuser for non-turbulent airflow. This pressure chamber allows ventilation or A/C air from the ductto enter the chamber which is compressed with a pressure plate. Thepressure plate is installed into the body of the diffuser, has aplurality of perforations and is mounted to the diffuser with aplurality of screws so as to create a pressure chamber larger than thedischarge chamber. The pressure chamber forces air into the dischargechamber which is formed by attaching a plate to the bottom of thediffuser with a plurality of perforations, which are larger than thoseperforations in the pressure plate.

Turbulence is eliminated since the air delivered into the space is notbeing propelled by a fan nor caused to bounce off deflectors or louvers.The direction is perpendicular to the discharge plate of the diffusersince the air is evenly “pressed” into the space across the entire faceof the discharge plate.

The diffuser may be a variety of shapes and sizes depending on theavailable apace in the ceiling and the needed proximity of the diffuserproviding make-up air to the hood requiring the make-up air. Examples ofshapes are rectangular, triangular, quarter circular and fullcylindrical. Air flow may be vertical or horizontal and the sheet metalof exposed diffusers may be covered to fit the space decor.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE INVENTION

FIG. 1( a) Plan view of the diffuser

FIG. 1( b) Elevation view of the diffuser

FIG. 1( c) Internal view of diffuser at section A-A

FIG. 2( a) Isometric view of rectangular diffuser

FIG. 2( b) Isometric internal view at section A-A of rectangulardiffuser

FIG. 3( a) Isometric view of triangular shaped diffuser with verticalair discharge

FIG. 3( b) Isometric internal view at section B-B of triangular diffuserwith vertical air discharge

FIG. 4( a) Isometric view of triangular shaped diffuser with horizontalair discharge

FIG. 4( b) Isometric internal view of triangular diffuser withhorizontal air discharge at section C-C

DETAILED DESCRIPTION OF THE INVENTION

The diffuser assembly for non-turbulent air flow replaces currently useddiffusers in applications where turbulence and uncontrolled dispersionof the air from a ventilation or A/C unit do not meet the requirementsof the system. Representative examples include: the use of ventilationor A/C as make-up air for grease exhaust hoods for cooking over openflame or heated grill surfaces; ventilation or A/C make-up air forexhaust hoods in laboratories where the hoods are used to exhaust toxicor noxious fumes; for the ventilation or A/C provided make-up air forspray booths where the over-spray is filtered and exhausted outside thefacility; and in meeting rooms, restaurants and auditoriums where lessturbulence reduces unwanted drafts and air currents. With the make-upair being provided with current diffusers that employ louvers ordeflector plates to direct air flow there is still turbulence thatcauses unwanted fumes from the heated grill or open flame cookingsurfaces, or laboratory tables, or spray booths to migrate into thespace outside of the exhaust hood.

Other inventions such as U.S. Pat. No. 5,733,191 (Lam), and, U.S. Pat.No. 4,726,285 (Kelly), disperse air into the space in the generaldirection described in the patent. Lam uses movable deflection plates inthe diffuser to direct the air flow, and Kelly uses dimples to dispersethe air laterally. Nothing in either of these inventions or othersimilar inventions, however, corrects the turbulence created by velocitypressure normal to air propelled by a fan only, nor do they achieve acontained and directed flow of air. In their patent application20080176506 by Gebke, et al, dated Jul. 24 2008, a different technologyis employed to achieve the desired non turbulent flow which involvesporous fabric material in lieu of pressure or discharge plates as usedin the invention. Use of porous fabric material as opposed to rigidplates present the problems of determining the needed porosity andaccounting for dust buildup on the material from air from theventilation or A/C system duct that could affect the air flow.

To achieve the desired turbulent free, controlled and directed air flow,velocity pressure, which exists in all air ducts, must be converted tostatic pressure which is then used to move the air from the ventilationor the A/C to the desired space. This conversion is accomplished bydirecting the ducted air under velocity pressure into a pressure chamberthat then presses air into a discharge chamber, and finally into thespace. The diffuser with the chambers as described is shown in FIG. 2(b). The resultant air being exited into the space is turbulent free andmono-directional, orthogonal to the plane of the exhaust chamber plate.

The diffuser is a rectangular box constructed of sheet metal with thecorners and sides welded, riveted or otherwise attached to each other toform a compartment that will not leak air under pressure. The length andwidth of the box are determined by the desired size of the diffuser faceand the required air volume. The height, length and width of he box aredimensioned such that there is sufficient volume and shape to allow forthe two required chambers: pressure and discharge. The top of the box isenclosed except for a hole to allow the introduction of air from theventilation and/or A/C duct to which the diffuser will be attached. Thepressure chamber is formed by attaching a pressure plate that is thesame dimensions as the length and width of the box and perforated with aplurality of holes such that the pressure chamber is larger than thelower, discharge chamber. The attachment of the pressure plate to thebox may be by a plurality of screws or by rivets or any other means ofattachment such that the pressure plate is parallel to the bottom of thebox. The discharge chamber is directly below and contiguous to thepressure chamber. The chamber is formed by installing a discharge platethat is the same dimensions as the length and width of the box andperforated with a plurality of holes which are larger than the holes inthe pressure plate, on the bottom of the box. Installation may be bybrackets and a plurality of screws, rivets or by any other means suchthat the discharge plate is parallel to the pressure plate and flat withrespect to the sides of the box. The construction of the rectangulardiffuser is shown in FIGS. 1( a), 1(b) and 1(c).

The basic rectangular diffuser is designed to be ceiling mounted and forthe discharge air to move straight down. The length and width dimensionsof the box are therefore partially determined by the type of ceiling andthe location of ceiling supports. Appropriate mounting hardwareincluding frames, brackets, support wires or other building coderequirements can be adapted to the diffuser in the same manner as themounting hardware is adapted to current air diffusers.

Other configurations of the box are possible including but not limitedto: triangular or quarter circular for mounting in corners or betweenthe vertical wall and the ceiling, fully cylindrical for mounting aroundsupport columns and below the ceiling allowing the air flow to behorizontal. FIGS. 3( a) and 3(b) show a triangular diffuser with airflow from the bottom for a vertical air flow. FIGS. 4( a) and 4(b) showthe triangular diffuser with horizontal air flow. Both of theseconfigurations allows the diffuser to be mounted in the corner of twoadjacent walls or below the ceiling abutting the ceiling and the wall.

The construction of the alternative shapes employs the same principle ofhaving a pressure chamber and perforated pressure plate, and acontiguous discharge chamber and perforated discharge plate, where thepressure chamber receives the ducted air from the ventilation or A/Csupply air. Where the alternative configurations are mounted in visibleareas and in the space, decorative coverings can be installed on theshowing sheet metal planes of the diffuser to blend with the spacedecor.

1. An air diffuser for non-turbulent air flow comprising: a rectangularsheet metal box, the corners and seams of which are constructed toprevent air leakage under pressure; with the top of the box solid exceptfor a hole to allow for connection to a ducted air supply; with the bodyof the box divided into contiguous chambers; with the upper or pressurechamber created by attaching a metal pressure plate containing aplurality of perforations parallel to the top of the box greater thanhalf of the height dimension of the box and having dimensions equal tothe length and width of the box; with the lower or discharge chambercreated by attaching a metal discharge plate containing a plurality ofperforations flush with the bottom of the box with the same dimensionsas the length and width of the box; with the bottom plate perforationslarger than the perforations in the center plate; and with the diffuserassembly including all necessary brackets and mounting parts to enableinstallation in the ceiling of a building.
 2. The diffuser fornon-turbulent air flow of claim 1, wherein the length of the box istwice the width.
 3. The diffuser for non turbulent air flow of claim 1,wherein the body of the box contains an inside sound and insulationlining.
 4. The diffuser for non-turbulent air flow of claim 1, whereinthe pressure plate containing a plurality of perforations is attached tothe inside of the box with a plurality of screws or rivets to bracketsin the box.
 5. The diffuser for non-turbulent air flow of claim 1,wherein the pressure plate containing a plurality of perforations isattached to the inside of the box by welding the plate to the sides ifthe box.
 6. The diffuser for non-turbulent air flow of claim 1, whereinthe discharge plate containing a plurality of perforations which arelarger than the perforations of the center plate is attached to thebottom of the box with a plurality of screws or rivets.
 7. The diffuserfor non-turbulent air flow of claim 1, wherein the box is triangularsuch that it will fit in the corner and against the walls of a room orspace and at ceiling height.
 8. The diffuser for non-turbulent air flowof claim 7, wherein the plate with a plurality of perforations connectedto the discharge chamber is the vertical hypotenuse side of thetriangular chamber and the bottom of the box is solid, creating air flowparallel to the ceiling.
 1. An air diffuser for non-turbulent air flowcomprising a pressure chamber connected to receive air from an airsource, one wall of said pressure chamber containing a plurality ofperforations, a discharge chamber mounted to receive air from saidpressure chamber through said perforated wall and having a dischargechamber wall formed with a plurality of perforations larger than thoseof the pressure chamber
 2. The air diffuser of claim 1 wherein: saiddischarge wall is parallel to the perforated wall of said pressurechamber
 3. The air diffuser of claim 1 wherein: said air diffuser is ahollow box having one surface formed with a means for connecting to anair source.
 4. The air diffuser of claim 1 wherein: said dischargechamber is contiguous with said pressure chamber.
 5. The air diffuser ofclaim 3 wherein: said one surface is the top of said diffuser.
 6. Theair diffuser of claim 3 wherein: said one surface is a side wall of saidair diffuser.
 7. The air diffuser of claim 3 wherein: said perforatedwall is parallel to said means.
 8. The air diffuser of claim 3 wherein:said perforated wall is perpendicular to said means.
 9. The air diffuserof claim 1 wherein: said air diffuser is rectangular.
 10. The airdiffuser of claim 1 wherein: said air diffuser is triangular
 11. The airdiffuser of claim 1 wherein: said discharge chamber has greater volumethan said pressure chamber.
 12. The air diffuser of claim 1 wherein: thelength and width of said pressure chamber and said discharge chamber arenot equal.
 13. The air diffuser of claim 1 wherein: the length and widthof said pressure chamber and said discharge chamber are equal.
 14. Theair diffuser of claim 1 wherein: one wall of said pressure chamber,other than said perforated wall, contains a hole for connection to anair source.
 15. The air diffuser of claim 10 wherein: the perforatedwall of said pressure chamber is internal t said triangular diffuser andparallel to said perforate wall of said discharge chamber.
 16. The airdiffuser of claim 10 wherein: one wall of said pressure chamber, otherthan said perforated wall, has a hole to allow air to enter from an airsource.
 17. The air diffuser of claim 1 wherein: the two chambers are ofdifferent shapes.
 18. The air diffuser of claim 1 wherein: theperforated wall of said pressure chamber and the perforated wall of saiddischarge chamber are parallel.